Just get a USB keyboard and plug it in the 360, works just fine.
The 360 version is dead easy to get up and running with a PC account by the way, it will ask you if you already have a PlayOnline account or want to create a new one, just stick in your existing details and that's it.
Only problem is the usual US/UK version thing, if you've been playing a US version of FFXI on PC then you won't be able to access the PlayOnline account administration stuff through a UK 360 version but you'll be able to log in and play the game just fine.
Hi everyone by the way!